Skipped most of the thread, largely repeating what I expect others to have said.
My advise:
RaceAll the 'base' races have strong advantages for a magician character, however I would generally stick with Human, or Elf if a charisma tradition. If using advanced races, either play a Pixie dedicated magician (ignore most/all physical skills), or a Formori augmented magician (
abuse skillwires horribly).
SkillsSpellcasting is (probably) your primary skill. Invest heavily, specialize as soon as you can in your focus (with Karma).
Counterspelling is your primary defense against magic. Invest heavily, specialize as soon as you can in Combat or Manipulation (with Karma).
Summoning allows you to operate remotely (astral overwatch/spirit bomb), also functioning as 'on demand' reinforcements & greatly expanding your versatility. Invest heavily.
Binding is generally less powerful overall than Summoning, but allows you to have more than one spirit at a time, greatly improving the reinforcement aspect of conjuring. Highly important for spirit based magicians, can be mostly ignored otherwise.
Ritual Spellcasting is a (potentially) very powerful ability, but is generally difficult to use effectively. Avoid until you have more experience playing a magician unless it is part of a concept.
Banishing is essentially useless. Stun/Manabolt are almost always more effective with significantly less cost & Drain.
Astral Combat is essentially useless. Stun/Manabolt are almost always more effective with significantly less cost. Only invest in it if for some reason you feel a need to defend
against it.
Assensing should have at least 1 point in it. Although not particularly important, it is a useful ability to have. Typically functions as an alternate for Perception (although usually less useful). It can provide additional information through aura reading.
SpellsStunbolt is used for nonlethal combat & astral combat. Low Drain, high damage potential. Multicast for less powerful but more precise 'AoE'.
Powerbolt is used for lethal combat & nonliving targets. Low Drain, high damage potential. Multicast for less powerful but more precise 'AoE'.
Mind Probe is ideal for interrogation, but is not subtle.
Heal can easily save members from dying mid-combat, stacks with First Aid (apply FA first) for post-combat healing.
Increased Reflexes is critical for any magician expecting to be in combat. Maintain with a sustaining focus.
Increase Willpower/DrainStat is useful if you expect to be overcasting, & are willing to trade a -2 penalty for more Drain resistance.
Modified Invisibility (realistic, multisense, physical) is an exceptional stealth spell with low drain. Pay attention to Object Resistance.
Trid Phantasm is the best all-around illusion. Pay attention to Object Resistance.
Fashion is superb for ettiquite & disguise.
Levitate functions as both telekinesis & fly. Versatile and useful.
Mind Control/Mob Mind effectively 'removes' opponents from combat, & can easily turn numbers in your favor.
Mana Static is the best general spell for magic control. Easily shuts down opposing magic users & spirits in confined spaces, forces repositioning in open spaces. Be careful about placing yourself in the area.
Physical Barrier can provide a bridge, area 'shield', & force Crash tests for vehicles. Generally weak but very versatile.
Mana Barrier provides an area defense against spells and hindrance to spirits & dual-natured creatures.
FociShielding Focus provides additional spell defense. Requires Shielding metamagic.
Power Focus increases your dice pool for all tests involving the Magic attribute, most notably Spellcasting & Summoning. As a dice pool modifier, you apply its full value to each dice pool separately if multicasting.
Centering Focus provides additional drain resistance. Requires Centering metamagic.
Sustaining Focus sustains a spell indefinitely (unless disrupted or dismissed). Specific to a single spell category.
Spellcasting Focus is a vastly more limited version of Power Focus. Not worth the cost.
Counterspelling Focus is a more limited version of Shielding Focus. (Usually) not worth the cost.
Summoning/Binding Focus are more limited versions of Power Focus. Not worth the cost.
Avoid other metamagic foci - generally useless.
MetamagicsQuickening conflicts with wards, which if the setting is being portrayed correctly, are common. Depending on GM, karma sink with no lasting benefit. Counters any attempt at stealth in secure areas. Avoid.
Nearly all other metamagics are useful & fair game. Exact order should be determined by campaign needs & player preference.